Problems with Sys.Services.AuthenticationService and client-side authentication

Hey there,

I'm trying to add client side authentication using Sys.Services.AuthenticationService.


I'm pretty much using the setup that is described here:

http://disturbedbuddha.wordpress.com/2007/11/19/a-client-side-ajax-login-for-aspnet/


 
However, whenever I call the "login" method, I recieve the following exception:


{"Message":"Authentication failed.","StackTrace":null,"ExceptionType":"System.InvalidOperationException"}


The post request that I sent is correctly formed as far as I can tell:

{"userName":"username","password":"password","createPersistentCookie":false }


But even w ...